The US motoring giant, which announced on 8 January it was to wind down the Saab business, is set to receive $74m in cash for the brand, as well as retaining shares in the marque to the value of $326m. The deal is expected to be finalised next month.
A Spyker spokesman said no decision had been taken on how the deal will affect Saab's agency roster, which includes Lowe, Draftfcb and Just Media. UK marketing is headed by David Pugh, and Saab spends about £10m on advertising in the UK.
Saab has been making losses since 2001, and in 2009, year-on-year revenue fell from €1.6bn to €1bn.
In the UK, sales of new Saabs fell 53% last year, while the number of registrations was down from 16,074 to 7,486, according to the Society for Motor Manufacturers and Traders (SMMT).
GM has been looking to sell the Swedish manufacturer for more than 12 months, having first acquired a 50% stake in Saab in 1989 and completing the deal in 2000.
In early 2009, GM Europe announced that Saab managing director Jan-Ake Jonsson would take responsibility for sales and marketing, allowing the marque to develop an independent marketing strategy.
In June, GM reached a tentative agreement to sell Saab to Scandinavian motor manufacturer Koenigsegg, but the deal fell through.